As is known in the art, one common approach to electronically control the valve actuation of an internal combustion engine is to have two electromagnets toggle an armature connected to the valve between an open position and a closed position. More particularly, referring to FIG. 1, when a first, here upper, one of the electromagnets is activated, the armature is attracted to the activated electromagnet thereby driving the valve to its closed position. Also, as the armature is attracted to the activated electromagnet, a first spring, in contact with the upper end of the armature is compressed. When the first electromagnet is deactivated, the first compressed spring releases it stored energy and drives the armature downward thereby driving the valve towards it open position. As the armature approaches the second, lower electromagnet, the second electromagnet is activated driving the valve to its full open position. It is noted that a second, lower spring becomes compressed during the process. After being fully open for the desired period of time, the second electromagnet is deactivated, and the lower spring releases its stored energy and thereby drives the armature towards its upper position, the first electromagnet is activated and the process repeats. Thus, the two electromagnets toggle the armature connected to the valve between an open or closed position where it is held, while the pair of springs is used to force the valve to move (oscillate) to the other state (FIG. 1).
One problem with the approach described above is that, because the armature and the valve both move, or stroke, in the same direction, a net force is produced on the engine during such stroke. The net force produced during an up-stroke is opposite to the net force produced during a down-stroke. These net upward-downward forces result in undesirable engine vibrations.